A tire attached to a wheel of various vehicles such as a compact vehicle, a heavy equipment vehicle and the like has a function of supporting a vehicle load, a function of transmitting power of a vehicle to a ground, and a function of reducing vibration and shock from the ground during driving of the vehicle.
A conventional pneumatic tire has an excellent cushioning effect against collision and bending/stretching due to its air pressure. However, when the tire is pricked or damaged by an external object, the air pressure is not maintained, which makes it difficult to realize the function of the tire. Further, when the tire is damaged during driving, handling and braking performance of the vehicle deteriorate and this may cause safety problems.
To that end, a non-pneumatic tire that does not require air filling has been developed. In the non-pneumatic tire, a spoke is provided between a tread and a wheel in order to realize the function of the air pressure in the conventional pneumatic tire. The non-pneumatic tire is generally used for low-speed vehicles or special purpose vehicles, and the cushioning effect, the driving performance and the like thereof are determined by a structure and a shape of the spoke.
A conventional non-pneumatic tire has good load supporting characteristics but poor noise, vibration and harshness characteristics. Or, the conventional non-pneumatic tire has improved noise, vibration and harshness characteristics but poor load supporting characteristics.
Therefore, it is required to develop a general-purpose spoke structure applicable to various vehicle environments due to its good load supporting characteristics, durability, and noise, vibration and harshness characteristics, and a non-pneumatic tire having such a spoke structure.